An old MUNI bus in San Francisco is getting a second life with a noble cause. Outfitted with toilets and showers, Lava Mae's refurbished bus will bring mobile bathrooms to homeless people around the city. The long-awaited bus will make its first rounds this weekend.

Homelessness in San Francisco is famously (and infamously) a growing concern. With thousands of homeless and just a handful of shower facilities for them, Lava Mae will be providing a much-needed service in the city. It'll park at various spots around San Francisco, drawing water from fire hydrants.

Doniece Sandoval, Lava Mae's founder, first got the idea two years ago. After securing an old bus from MUNI, she's raised money—through crowdfunding and corporate sponsors like Google—to outfit the bus with two full-service bathrooms. If all goes well, she hopes to have three more shower buses up and running.

For better or for worse, the fates of public sanitation and homelessness in San Francisco—and elsewhere—are intertwined. "For at least a decade, bathrooms have stood in for the city's anxieties about homelessness, public utilities, and the changing economy," wrote Rachel Swan in an excellent piece on public bathrooms in SF Weekly. That the city's shiny JCDecaux public toilets—with their futuristic-sounding self-cleaning cycles—have turned into dens of drug use and prostitution is a symptom of the city's problems.

Lava Mae isn't going to solve the root cause of homelessness, but it does very directly address a real issue faced by the homeless. And it's an idea San Franciscans who love to complain about smelly streets can certainly get behind it. [CBS San Francisco, SFist]

Doniece Sandoval in front of the Lava Mae bus. All photos by Kena Frank